In automotive usage, it is commonplace to mount two independently operable window panels within the same door structure, one being the main windowand the other a small vent window. The regulator mechanisms for each window panel in some cases are generally totally independent of one another and therefore require two separate, spaced-apart operating mechanisms, most frequently to provide one slide movement and one rotational movement.
In other forms, slidable window panels operable in sequence from a single common operator are known. The panels may thus be controlled from a common regulator mechanism.
Objection to such sequential controls was raised by customers based on the inflexible nature of the sequence. As a result, it is desired that a regulator mechanism be devised which allows movement of the two panels independently of one another under the selective control of the user.